In the age of the Internet, you might find yourself clicking "reply," typing up a quick response, and hitting "send" without giving so much as a thought about what you've just written. But experts agree that your e-mail behavior has the potential to sabotage your reputation both personally and professionally. Inc.com got in touch with some of the industry's most seasoned e-mail experts and had them weigh in on how to perfect your e-mail etiquette.

1. Only discuss public matters. We've all heard the stories about a "private" e-mail that ended up being passed around to the entire company, and in some cases, all over the Internet. One of the most important things to consider when it comes to e-mail etiquette is whether the matter you're discussing is a public one, or something that should be talked about behind closed doors. Ask yourself if the topic being discussed is something you'd write on company letterhead or post on a bulletin board for all to see before clicking "send." --Judith Kallos, author of E-Mail Etiquette Made Easy, E-Mail: The Manual, and E-Mail: A Write It Well Guide

2. Briefly introduce yourself. Do not assume the person receiving your e-mail knows who you are, or remembers meeting you. If you are uncertain whether the recipient recognizes your e-mail address or name, include a simple reminder of who you are in relation to the person you are reaching out to; a formal and extensive biography of yourself is not necessary. --Peggy Duncan, personal productivity expert and author of Conquer Email Overload with Better Habits, Etiquette, and Outlook 2007

3. Don't "e-mail angry." E-mailing with bad news, firing a client or vendor, expressing anger, reprimanding someone, disparaging other people in e-mails (particularly if you're saying something less than kind about your boss) are all major no-no's. Because e-mail can seem so informal, many people fall into this trap. Always remember that e-mail correspondence lasts forever. --Lindsey Pollak, career and workplace expert, e-mail etiquette consultant, and author of Getting From College to Career

4. Use exclamation points sparingly. The maximum number of exclamation points in a business e-mail? One. Otherwise, you risk looking childish and unprofessional. --Pollak

5. Be careful with confidential information. Refrain from discussing confidential information in e-mails such as someone's tax information or the particulars of a highly-sensitive business deal. Should the e-mail get into the wrong person's hands, you could face serious - even legal - repercussions. --Peter Post, director of the Burlington, Vermont-based Emily Post Institute, which offers etiquette advice and answers to manners questions such as wedding etiquette, parenting issues and table manners.

6. Respond in a timely fashion. Unless you work in some type of emergency capacity, it's not necessary to be available the instant an e-mail arrives. Depending on the nature of the e-mail and the sender, responding within 24 to 48 hours is acceptable. --Duncan

7. Refrain from sending one-liners. "Thanks," and "Oh, OK" do not advance the conversation in any way. Feel free to put "No Reply Necessary" at the top of the e-mail when you don't anticipate a response. --Duncan

8. Avoid using shortcuts to real words, emoticons, jargon, or slang. Words from grown, business people using shortcuts such as "4 u" (instead of "for you"), "Gr8" (for great) in business-related e-mail is not acceptable. If you wouldn't put a smiley face or emoticon on your business correspondence, you shouldn't put it in an e-mail message. Any of the above has the potential to make you look less than professional. --Duncan

9. Keep it clean. Nothing annoys recipients more than when people reply and leave the messages messy, for example, an e-mail chain that includes excessive carets (>>>), or pages and pages of e-mail addresses that weren't protected using Bcc. You can get rid of carets by selecting the text, Ctrl+F to use the Find and Replace command to find a caret and replace all of them with nothing. You can get rid of all the e-mail addresses just by deleting. Clean it up, then send it. --Duncan

10. Be clear in your subject line. With inboxes being clogged by hundreds of e-mails a day, it's crucial that your subject line gets to the point. It should be reasonably simple and descriptive of what you have written about. Expect that any e-mail with a cute, vague, or obscure subject will get trashed. Also, proof your subject line as carefully as you would proof the rest of the e-mail. --Post

11. Don't get mistaken for Spam. Avoid subject lines that are in all caps, all lower case, and those that include URLs and exclamation points - which tend to look like Spam to the recipient. --Judith Kallos, author of E-Mail Etiquette Made Easy, E-Mail: The Manual, and E-Mail: A Write It Well Guide

12. Your subject line must match the message. Never open an old e-mail, hit Reply, and send a message that has nothing to do with the previous one. Do not hesitate to change the subject as soon as the thread or content of the e-mail chain changes. --Peggy Duncan, personal productivity expert and author of Conquer Email Overload with Better Habits, Etiquette, and Outlook 2007

13. Provide a warning when sending large attachments. Sending unannounced large attachments can clog the receiver's inbox and cause other important e-mails to bounce. If you are sending something that is over 500KB, senders should ask, 'Would you mind if I sent you an attachment? When would be the best time for you?' --Kallos

14. No more than two attachments, and provide a logical name. Unless it's been specifically requested, refrain from sending a message with more than two attachments. Also, give the attached file(s) a logical name so the recipient knows at a glance the subject and the sender. --Duncan

15. Send or copy others only on a need to know basis. Before you click Reply All or put names on the Cc or Bcc lines, ask yourself if all the recipients need the information in your message. If they don't, why send it? Take time to send your messages to the right people. --Duncan

16. Beware of the "reply all." Do not hit "reply all" unless every member on the e-mail chain needs to know. You want to make sure that you are not sending everyone on a list your answer-;whether they needed to know or not. --Duncan

17. Pick up the phone. When a topic has lots of parameters that need to be explained or negotiated and will generate too many questions and confusion, don't handle it via e-mail. Also, e-mail should not be used for last minute cancellations of meetings, lunches, interviews, and never for devastating news. If you have an employee or a friend you need to deliver bad news to, a phone call is preferable. If it's news you have to deliver to a large group, e-mail is more practical. --Duncan

18. Evaluate the importance of your e-mail. Don't overuse the high priority option. If you overuse this feature, few people will take it seriously. A better solution is to use descriptive subject lines that explain exactly what a message is about. --Duncan

19. Maintain privacy. If you're sending a message to a group of people and you need to protect the privacy of your list, you should always use "Bcc." Additionally, avoid giving out e-mail addresses to a third party (such as an Evite, newsletter, etc). Make sure that addresses you willingly hand over to third parties stay with them, especially when the service they're offering is free. --Duncan

20. Keep it short and get to the point. The long e-mail is a thing of the past. Write concisely, with lots of white space, so as to not overwhelm the recipient. Make sure when you look at what you're sending it doesn't look like a burden to read - feel free to use bullet points. The person reading your e-mail should not have to dig through several paragraphs in order to figure out what you're asking. You should state the purpose of the e-mail within the first two sentences. Be clear, and be up front. --Lindsey Pollak, career and workplace expert, e-mail etiquette consultant, and author of Getting From College to Career

21. Know your audience. Your e-mail greeting and sign-off should be consistent with the level of respect and formality of the person you're communicating with. Also, write for the person who will be reading it - if they tend to be very polite and formal, write in that language. The same goes for a receiver who tends to be more informal and relaxed. --Lindsey Pollak, career and workplace expert, e-mail etiquette consultant, and author of Getting From College to Career

22. Always include a signature. You never want someone to have to look up how to get in touch with you. If you're social media savvy, include all of your social media information in your signature as well. Your e-mail signature is a great way to let people know more about you, especially when your e-mail address is does not include your full name or company. --Pollak

23. Only use an auto-responder when necessary. An automatic response that says, "Thank you for your e-mail message. I will respond to you as soon as I can" is useless. However, one thing these messages do great is alert spammers that your e-mail is real and that they can add you to their spam list. --Peggy Duncan, personal productivity expert and author of Conquer Email Overload with Better Habits, Etiquette, and Outlook 2007

24. Train your staff. Business owners should make sure their staff is trained in e-mail communications - don't assume they know what they're doing, and what is considered professional. Set up e-mail standards that everyone at the company should abide by. --Pollak

25. Your e-mail is a reflection of you. Every e-mail you send adds to, or detracts from your reputation. If your e-mail is scattered, disorganized, and filled with mistakes, the recipient will be inclined to think of you as a scattered, careless, and disorganized businessperson. Other people's opinions matter and in the professional world, their perception of you will be critical to your success. --Peter Post, director of the Burlington, Vermont-based Emily Post Institute, which offers etiquette advice and answers to manners questions such as wedding etiquette, parenting issues and table manners.

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